1. Field of the Invention
The present invention relates to a coupling for the production of a releasable connection between a medical, in particular a dental, handpiece part and a supply hose, and for the transmission of current and if applicable further supply media from the supply hose to the handpiece part.
2. Related Technology
For connection between a dental handpiece part, which may be an angled piece for example, and a supply hose, which serves for the supply of the handpiece part with supply media, such as for example air, water, current or light, it is known to provide a coupling which consists of two coupling elements, wherein one of the two coupling elements is arranged on the handpiece part and the other on the supply hose. For connection, these two coupling elements must be inserted into one another in a certain relative position, in order to connect the media lines for air, water etc. Then, to secure the connection, a lock nut arranged on the one coupling element must then be screwed onto a thread on the other coupling element.
For the production of this connection it is thus necessary that initially the two coupling elements are brought to a certain relative position. In addition, a separate operating step has to be carried out to secure the connection.
A coupling of the kind described above is known from EP 0 185 290 B1, for example. With this known coupling, ring-like channels are provided for the transmission of air and water, which actually make possible a media transmission in any rotational position, however there are used for current transmission inter alia two end face contact pairs. Through this a corresponding current transmission is possible only in a suitable rotational disposition of the two coupling elements, which—as described above—makes handling more difficult.
Further couplings for dental handpieces are known from EP 1 145 688 A1 and DE 32 15 207 A1, in which current transmission is effected with the aid of ring-like sliding contacts. Although these make possible a current transmission in any disposition of the coupling elements with respect to one another, and thus simplify handling, plug contacts are however to be preferred for a durable and reliable current transmission.